3. Uppercase/Lowercase.asm

.MODEL SMALL
.STACK 100H
.DATA
.CODE
INCLUDE 'EMU8086.INC'

START:
MOV AH, 1
INT 21H


CMP AL, 'A'
JGE CHECK
JL END_IF

CHECK:
CMP AL, 'Z'
JLE PRINT
JG END_IF

PRINT:
MOV AH, 2
MOV DL, AL
INT 21H
JMP START

END_IF:
MOV AH, 4CH
INT 21H